Former World Cup ski champion Bill Koch,...

Former World Cup ski champion Bill Koch, 36, disqualified in his first try at making the U.S. Olympic team for the fourth time, said he will be watching directional signs more closely when the Olympic tryouts resume at Giants Ridge Ski Area in Biwabik, Minn.

Koch, the only U.S. skier to win an Olympic medal in cross-country, is coming back after five years of retirement. He was disqualified Saturday for using a skating step after taking a wrong turn near the end of the 30-kilometer classical technique (diagonal stride) race.

John Aalberg of Salt Lake City won the men’s 30K classic race and Nancy Fiddler of Crowley Lake, Calif., won the women’s 15K for her 12th national title.